Gain control method for a broadband inductorless low noise amplifier

ABSTRACT

A mobile device comprising an antenna, a receiver coupled to the antenna, and a transmitter coupled to the antenna, wherein the receiver, the transmitter, or both comprise a low noise amplifier comprising an adjustable gain and a variable impedance controller, and wherein the low noise amplifier is configured to sink current and to adjust a shunt resistance substantially simultaneously. Included is a method comprising receiving an electrical signal, substantially simultaneously adjusting an input impedance and a gain factor, amplifying the electrical signal, thereby producing an amplified signal, and outputting the amplified signal.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO A MICROFICHE APPENDIX

Not applicable.

BACKGROUND

One part in a radio transceiver is a radio frequency (RF) low noiseamplifier (LNA), which may be used in either a receiver or a transmitterof the radio transceiver. The performance requirements for the RF LNAcomprise low noise contribution, high gain amplification, and goodlinearity. For example, the RF LNA in a receiver will boost anelectrical signal above a noise threshold of subsequent stages in thereceiver while contributing very little noise to the electrical signal.

Impedance matching between the RF LNA and filters and/or other devicesis needed in order to provide proper frequency response for the filtersand/or other devices connected to the RF LNA. Conventional devices,systems, and methods may be insufficient to provide adjustable gaincontrol while maintaining a substantially constant input impedance. Assuch, devices, systems, and methods for providing adjustable gaincontrol while maintaining the input impedance are needed.

SUMMARY

In one embodiment, the disclosure includes a mobile device comprising anantenna, a receiver coupled to the antenna, and a transmitter coupled tothe antenna, wherein the receiver, the transmitter, or both comprise alow noise amplifier comprising an adjustable gain and a variableimpedance controller, and wherein the low noise amplifier is configuredto sink current and to adjust a shunt resistance substantiallysimultaneously.

In another embodiment, the disclosure includes a method comprisingreceiving an electrical signal, substantially simultaneously adjustingan input impedance and a gain factor, amplifying the electrical signal,thereby producing an amplified signal, and outputting the amplifiedsignal.

In yet another embodiment, the disclosure includes an amplifiercomprising an input connection, an output connection, a variableimpedance controller coupled to the input connection and the outputconnection, wherein the variable impedance controller is configured tohave an adjustable impedance, a current source, a first transistorcomprising a first interface coupled to the current source, a secondinterface coupled to the output connection, and a third interfacecoupled to the input connection and is configurable between a firststate and a second state, wherein when the first transistor is in thefirst state, the first transistor prevents a route of electrical currentvia the first interface and the second interface of the firsttransistor, and wherein when the first transistor is in the secondstate, the first transistor allows a route of electrical current via thefirst interface and the second interface of the first transistor, aground, and a second transistor comprising a first interface coupled tothe current source, a second interface coupled to the ground, and acontrol interface and is configurable between a first state and a secondstate, wherein when the second transistor is in the first state, thesecond transistor prevents a route of electrical current via the firstinterface and the second interface of the second transistor, and whereinwhen the second transistor is in the second state, the second transistorallows a route of electrical current via the first interface and thesecond interface of the second transistor.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of this disclosure, reference is nowmade to the following brief description, taken in connection with theaccompanying drawings and detailed descriptions, wherein like referencenumerals represent like parts.

FIG. 1 is a schematic diagram of an embodiment of a mobile device;

FIG. 2 is a schematic diagram of an embodiment of an electronic circuitimplementation of a receiver;

FIG. 3 is a schematic diagram of an embodiment of an electronic circuitimplementation of a transmitter;

FIG. 4 is a schematic view of an embodiment of an electronic circuitimplementation for a low noise amplifier;

FIG. 5 is a partial schematic view of an embodiment of an electroniccircuit implementation for an adjustable low noise amplifier;

FIG. 6 is a partial schematic view of an embodiment of a variableimpedance controller;

FIG. 7 is a flow chart of an embodiment of an amplification method; and

FIG. 8 is a chart of an impedance response of an adjustable low noiseamplifier.

DETAILED DESCRIPTION OF THE EMBODIMENTS

It should be understood at the outset that, although an illustrativeimplementation of one or more embodiments are provided below, thedisclosed systems and/or methods may be implemented using any number oftechniques, whether currently known or in existence. The disclosureshould in no way be limited to the illustrative implementations,drawings, and techniques illustrated below, including the exemplarydesigns and implementations illustrated and described herein, but may bemodified within the scope of the appended claims along with their fullscope of equivalents.

Disclosed herein are embodiments of an adjustable low noise amplifier(ALNA), a mobile device comprising an ALNA, and methods using the same.In an embodiment, the ALNA may be employed to provide an adjustable gainwhile also substantially maintaining its input impedance, therebymaintaining the frequency response characteristics of other components(e.g., filters) connected to the ALNA (e.g., in a receiver, in atransmitter, and/or in a mobile device), as will be disclosed herein.

Referring to FIG. 1, an embodiment of an operating environment of anALNA is illustrated. In an embodiment, the operating environmentgenerally comprises a plurality of functional units associated with amobile device, as will be disclosed herein.

In an embodiment as illustrated in FIGS. 1-6, the mobile device 100 maycomprise a plurality of functional units. In an embodiment, a functionalunit (e.g., an integrated circuit (IC)) may perform a single function,for example, serving as an amplifier or a buffer. Additionally oralternatively, the functional unit may perform multiple functions on asingle chip. In an embodiment, the functional unit may comprise a groupof components (e.g., transistors, resistors, capacitors, diodes, and/orinductors) on an IC which may perform a defined function. In anembodiment, the functional unit may comprise a specific set of inputs, aspecific set of outputs, and an interface (e.g., an electricalinterface, a logical interface, and/or other interfaces) with otherfunctional units of the IC and/or with external components. In someembodiments, the functional unit may comprise repeat instances of asingle function (e.g., multiple flip-flops or adders on a single chip)or may comprise two or more different types of functional units whichmay together provide the functional unit with its overall functionality.For example, a microprocessor may comprise functional units such as anarithmetic logic unit (ALU), one or more floating point units (FPU), oneor more load or store units, one or more branch prediction units, one ormore memory controllers, and other such modules. In some embodiments,the functional unit may be further subdivided into component functionalunits. For example, a microprocessor as a whole may be viewed as afunctional unit of an IC, for example, if the microprocessor sharescircuit with at least one other functional unit (e.g., a cache memoryunit).

The functional unit may comprise, for example, a general purposeprocessor, a mathematical processor, a state machine, a digital signalprocessor, a video processor, an audio processor, a logic unit, a logicelement, a multiplexer, a demultiplexer, a switching unit, a switchingelement an input/output (I/O) element, a peripheral controller, a bus, abus controller, a register, a combinatorial logic element, a storageunit, a programmable logic device, a memory unit, a neural network, asensing circuit, a control circuit, a digital to analog converter, anoscillator, a memory, a filter, an amplifier, a mixer, a modulator, ademodulator, and/or any other suitable devices as would be appreciatedby one of ordinary skill in the art.

In the embodiments of FIGS. 1-6, the mobile device 100 may comprise aplurality of distributed components and/or functional units and eachfunctional unit may communicate with via a suitable signal conduit, forexample, via one or more electrical connections, as will be disclosedherein.

In the embodiment of FIG. 1, the operating environment comprises mobiledevice 100 comprising a plurality of interconnected functional units,for example, for transmitting and/or receiving one or more wirelesssignals. In the embodiment of FIG. 1, the mobile device 100 maygenerally comprise various functional units including, but not limitedto one or more antennas 128, a transmitter 114, a receiver 112, a localoscillator 126, a logical unit 120, a data storage device 110, a screen116, a microphone 118, a speaker 122, a plurality of input and/or output(I/O) ports 124, arranged as shown in FIG. 1. In such an embodiment, themobile device 100 is configured such that a wireless signal may bereceived, transmitted, and/or undergo signal processing by the mobiledevice 100. While FIG. 1 illustrates a particular embodiment of anoperating environment in which an ALNA may be employed and/or aparticular configuration of functional units with which an ALNA may beassociated, one of ordinary skill in the art, upon viewing thisdisclosure, will appreciate that an ALNA as will be disclosed herein maybe similarly employed in alternative operating environments and/or withalternative configurations of mobile device functional units.

In an embodiment, the mobile device 100 may comprise one or moreantennas 128, which may be exterior to and/or interior to the mobiledevice 100. In an embodiment, the antennas 128 may be configured tointerface and/or to couple to the transmitter 114, the receiver 112,and/or any other functional units of the mobile device 100, as will bedisclosed herein. For example, in the embodiment of FIG. 1, the outputof the antennas 128 may be electrically connected to an input of thetransmitter 114 (e.g., via electrical connection 150) and/or to an inputof the receiver 112 (e.g., via electrical connection 150).

In such an embodiment, the antennas 128 may be configured to receiveand/or to transmit a wireless signal to/from the mobile device 100. Inan embodiment, the antenna 128 may comprise a patch antenna, amicrostrip antenna, a loop antenna, an omni directional antenna, aplanar inverted-F antenna (PIFA), a folded inverted conformal antenna(FICA), a monopole antenna, any other suitable antenna as would beappreciated by one of ordinary skill in the art upon viewing thisdisclosure, or combinations thereof. Additionally, in an embodiment, theantennas 128 may be configured to be responsive to one or morepredetermined frequency bands. For example, the antennas 128 may beconfigured to be responsive to a wireless signal (e.g., a RF signal)within a predetermined frequency band, for example, within the 700 Band,the 800 band, the 850 band, the 1400 band, the personal communicationservices (PCS) band, the advanced wireless services (AWS) band, thebroadband radio services (BRS)/emergency broadcast system (EBS) band,long term evolution (LTE) band, any other suitable frequency band aswould be appreciated by one of ordinary skill in the art upon viewingthis disclosure, or combinations thereof. In an additional oralternative embodiment, the antennas 128 may be configured to beselectively tuned to be responsive to one or more frequency bands, forexample, by an antenna switch, as will be disclosed herein.

In the embodiment of FIG. 1, the logic unit 120 may be electricallyconnected to the transmitter 114 (e.g., via electrical connection 152),the receiver 112 (e.g., via electrical connection 154), the screen 116(e.g., via electrical connection 156), the microphone 118 (e.g., viaelectrical connection 160), the speaker 122 (e.g., via electricalconnection 162), the data storage device 110 (e.g., via electricalconnection 158), and the I/O ports 124 (e.g., via electrical connection164).

In an embodiment, the logic unit 120 comprises an electronic circuitconfigured to perform arithmetic operations and/or logical operations.Additionally, the logic unit 120 may be configured to control the flowof data through the mobile device 100 and/or coordinate the activitiesof one or more functional units of the mobile device 100. For example,the logic unit 120 may be configured to be coupled with and/or tocontrol data transmission between the transmitter 114, the receiver 112,the microphone, 118, the speaker 122, and/or any other functional unitsof the mobile device 100. In an additional or alternative embodiment,the logic unit 120 may further comprise a digital signal processor (DSP)and may be configured to manipulate, to modify, and/or to improve adigital electrical signal, for example, a digital electrical signal fromthe receiver 112.

In an embodiment, the data storage device 110 may be generallyconfigured to store information (e.g., data) for the mobile device 100.In such an embodiment, the mobile device 100 may be configured to readand/or to write data to one or more memory cells of the data storagedevice 110. In an embodiment, the data storage device 110 may comprise aread only memory (ROM), a random access memory (RAM), a flash memory, anexternal memory (e.g., a secure digital (SD) card), any suitable type ofmemory device as would be appreciated by one of ordinary skill in theart upon viewing this disclosure, or combinations thereof.

In an embodiment, the screen 116 may be configured to present visualinformation to a mobile device user. For example, in such an embodiment,the screen 116 may comprise an liquid crystal display (LCD), a lightemitting diode (LED) display, an organic light emitting diode (OLED)display, an active-matrix organic light emitting diode (AMOLED) display,a color super twisted nematic (CSTN) display, a thin film transistor(TFT) display, a thin film diode (TFD) display, and/or any othersuitable type of display as would be appreciated by one of ordinaryskill in the art upon viewing this disclosure. In an additional oralternative embodiment, the screen may further comprise a capacitivetouchscreen or a resistive touchscreen.

In an embodiment, the microphone 118 and the speaker 122 may each beconventional as would be appreciated by one of ordinary skill in the artupon viewing this disclosure. For example, the microphone 118 may beconfigured to convert a voice signal to an electrical signal (e.g., ananalog signal or a digital signal). Additionally, in an embodiment, thespeaker 122 may be configured to convert an analog electrical signalinto an audible signal.

In an embodiment, the plurality of I/O ports 124 may be generallyconfigured to transmit electrical signals and/or data signals betweenthe mobile device 100 and external hardware (e.g., an electrical outlet,a computer). For example, the I/O ports 124 may comprise a plurality ofelectrical contacts and may be mated with suitable interface as would beappreciated by one of ordinary skill in the art up on viewing thisdisclosure.

Additionally, in an embodiment, the mobile device 100 may furthercomprise one or more dedicated buttons and/or soft keys. For example,the one or more soft keys may be configured to allow the user to providean input to the mobile device 100.

In an embodiment, the local oscillator 126 may be configured tointerface and/or to couple to a mixer, for example, a mixer of thetransmitter 114 (e.g., via electrical connection 166) and/or a mixer 126of the receiver 112 (e.g., via electrical connection 168), as will bedisclosed herein.

In an embodiment, the local oscillator 126 may be configured to producea repetitive oscillating electronic signal (e.g., a sine wave or asquare wave). For example, the local oscillator 126 may convert a directcurrent signal (e.g., from a power supply) to an alternating currentsignal. In an embodiment, the local oscillator 126 may be configured toproduce an electronic signal oscillating at a frequency between 100kilohertz (kHz) to 100 gigahertz (GHz). In the embodiment where thelocal oscillator 126 is configured to produce a square wave signal, thelocal oscillator 126 may also be configured to have a variable dutycycle. For example, the local oscillator 126 may be configured toproduce a square wave signal with a 25% duty cycle. In an alternativeembodiment, the local oscillator 126 may be configured to produce anyother suitable signal as would be appreciated by one of ordinary skillin the art upon viewing this disclosure.

In an embodiment, the transmitter 114 may comprise a plurality ofinterconnected functional units (e.g., a low noise amplifier, a mixer, afilter, etc.) and may be configured to be coupled with one or moreantennas 128 to produce an electrical signal and/or a RF signal. Forexample, the transmitter 114 may be configured to receive a data signalfrom the mobile device 100 and to transmit the data signal via a RFsignal. In an embodiment, the transmitter 114 may be configured toproduce and/or transmit a wireless signal (e.g., a RF signal) within the700 Band, the 800 band, the 850 band, the 1400 band, the PCS band, theAWS band, the BRS/EBS band, or any other suitable frequency band aswould be appreciated by one of ordinary skill in the art upon viewingthis disclosure, or combinations thereof. Additionally, in anembodiment, the transmitter 114 may comprise shared functional unitsand/or electrical connections to other functional units of the mobiledevice 100, for example, an electrical connection with the receiver 112via the electrical connection 170.

In an embodiment, the receiver 112 may comprise a plurality ofinterconnect functional units (e.g., a low noise amplifier, a mixer, afilter, etc.) and may be configured to be coupled with one or moreantennas 128 to receive an electrical signal and/or a RF signal, as willbe disclosed herein. For example, the receiver 112 may be configured toreceive an electrical signal (e.g., a voltage signal or a currentsignal) from the antenna 128 and may be configured to convert and/or toextract a data signal from the electrical signal, as will be disclosedherein. Additionally, in an embodiment, the receiver 112 may compriseshared functional units and/or electrical connections to otherfunctional units of the mobile device 100, for example, an electricalconnection with the transmitter 114 via the electrical connection 170.

In the embodiment of FIG. 2, an implementation of the receiver 112 isillustrated. It is noted that in such an embodiment the circuit levelimplementation is provided for illustrative purposes and that a personskilled in the relevant arts will recognize suitable alternativeembodiments, configurations, and/or arrangements of such functionalunits which may be similarly employed. Any such functional unitembodiments may conceivably serve as elements of the disclosedimplementation.

In the embodiment of FIG. 2, the receiver 112 may generally comprise anantenna switch 224, a high-Q filter 202, a duplexer 204, an ALNA 206 a,a mixer 210, and a filter 214, arranged as shown in FIG. 2. Although theembodiment of FIG. 2 illustrates a receiver 112 comprising multipledistributed components (e.g., an antenna switch 224, a high-Q filter202, a duplexer 204, an ALNA 206 a, a mixer 210, and a filter 214, eachof which comprises a separate, distinct component), in an alternativeembodiment, a similar receiver 112 may comprise similar components in asingle, unitary component. Alternatively, the functions performed bythese components (e.g., the antenna switch 224, the high-Q filter 202,the duplexer 204, the ALNA 206 a, the mixer 210, and the filter 214) maybe distributed across any suitable number and/or configuration of likecomponentry, as will be appreciated by one of ordinary skill in the artwith the aid of this disclosure.

In the embodiment of FIG. 2, the antenna switch 224 may be configured toreceive an electrical signal from the antenna 128 (e.g., via electricalconnection 150) and to communicate the electrical signal with the high-Qfilter 202 (e.g., via electrical connection 250). In an embodiment, theantenna switch 224 may be controllable and/or configured to selectivelyprovide one or more electrical channels between the antenna 128 and thehigh-Q filter 202. For example, the antenna switch 224 may be controlledby the logical unit 120 and may be configured to provide one or moreelectrical channels dependent on a frequency band of interest (e.g., thePCS band, the AWS band, the BRS band, etc.).

In the embodiment of FIG. 2, the high-Q filter 202 may be configured toreceive an electrical signal from the antenna switch 224 (e.g., viaelectrical connection 250) and to output a band-pass filtered electricalsignal to the duplexer 204 (e.g., via electrical connection 252). In anembodiment, the high-Q filter 202 may be a passive filter and maycomprise one or more passive electrical components (e.g., one or morecapacitors, one or more resistors, one or more inductors, etc.). In analternative embodiment, the high-Q filter 202 may be an active filterand may comprise one or more active electrical components (e.g., one ormore transistors, one or more integrated circuits). For example, thehigh-Q filter 202 may be a passive filter and comprise one or morecapacitors and resistors and thereby form a RC filter. In an alternativeembodiment, any suitable type and/or configuration may be employed aswould be appreciated by one of ordinary skill in the art upon viewingthis disclosure.

In an embodiment, the high-Q filter 202 may be configured to filterfrequencies above a first predetermined cut-off frequency and below asecond predetermined cut-off frequency. For example, the high-Q filter202 may be configured as a band-pass filter and may be configured tolimit the bandwidth of the electrical signal and/or to remove and/orsubstantially reduce the frequency content outside of the firstpredetermined cut-off frequency and the second predetermined cut-offfrequency, thereby generating the band-pass filtered electrical signal.

In an embodiment, the duplexer 204 may be configured to receive aband-pass filtered electrical signal from the output of the high-Qfilter 202 (e.g., via electrical connection 252) and to output theband-pass filtered electrical signal to the input of the ALNA 206 a(e.g., via electrical connection 254). In an additional or alternativeembodiment, the duplexer 204 may further comprise an electricalconnection to the transmitter 114 in FIG. 1 (e.g., via electricalconnection 170 in FIG. 1). In an embodiment, the duplexer 204 may beconfigured to allow bi-directional electrical communication, forexample, between the receiver 112 and the antenna 128 and/or thetransmitter 114 in FIG. 1.

In an embodiment, as illustrated in FIG. 2, where the ALNA 206 iselectrically connected to one or more functional units (e.g., aduplexer) of the mobile device 100, an electrical signal (e.g., aband-pass filtered signal) may be received by the ALNA 206 a. Forexample, the electrical signal may comprise a data signal received bythe one or more antennas 128. In the embodiment of FIG. 2, the ALNA 206a may be configured to receive a band-pass electrical signal from theoutput of the duplexer 204 (e.g., via electrical connection 254) and tooutput an amplified electrical signal to the input of the mixer 210(e.g., via electrical connection 256), as discussed below.

In an embodiment, the electrical signal may pass through the ALNA 206 aand experience a gain (e.g., a voltage gain) and, thereby form anamplified electrical signal. For example, the electrical signal mayexperience a gain of about 1,000 and the voltage swing of the electricalsignal may increase from about 1 millivolt (mV) to about 1 volt (V). Inan alternative embodiment, the electrical signal may experience anysuitable gain as established by the ALNA 206 a and/or a logic unit, asdisclosed herein.

In the embodiment of FIG. 2, the mixer 210 may be configured to receivethe amplified electrical signal from the ALNA 206 a (e.g., viaelectrical connections 256) and to output a mixed signal to the filter214 (e.g., via electrical connections 258). Additionally, in anembodiment, the mixer 214 may be configured to receive an input signalfrom the local oscillator 126 (e.g., via electrical connections 168).For example, the mixer 210 may be coupled to a 25% duty cycle localoscillator and may be configured to receive a differential in-phasesignal and a quadrature signal from the local oscillator. In anembodiment, the mixer 210 may be a passive mixer and may generallycomprise one or more diodes. In an alternative embodiment, the mixer 210may be an active mixer and may generally comprise one or more diodesand/or one or more transistors. In an alternative embodiment, anysuitable type and/or configuration may be employed as would beappreciated by one of ordinary skill in the art upon viewing thisdisclosure.

In an embodiment, the mixer 210 may be generally configured to generatea new frequency (e.g., carrier frequency) dependent on the carrierfrequency of the input signal provided via the ALNA 206 a and/or asignal from the local oscillator 126. For example, the mixer 210 may beconfigured to perform a frequency translation and may reduce or increasethe carrier frequency (e.g., down-convert or up-convert) of an inputsignal (e.g., the amplified electrical signal). In an embodiment, themixer 210 may be configured to have a band-pass frequency response.

In an embodiment, the filter 214 may be configured to receive a mixedsignal from the mixer 210 (e.g., via electrical connection 258) and tooutput a filtered electrical signal (e.g., to the logic unit 120 inFIG. 1) via electrical connection 154. In an embodiment, the filter 214may be a passive filter and may comprise one or more passive electricalcomponents (e.g., one or more capacitors, one or more resistors, one ormore inductors, etc.). In an alternative embodiment, the filter 214 maybe an active filter and may comprise one or more active electricalcomponents (e.g., one or more transistors, one or more integratedcircuits). For example, the filter 214 may be a passive filter andcomprise one or more capacitors and resistors and thereby form aresistor and capacitor (RC) filter. In an alternative embodiment, anysuitable type and/or configuration may be employed as would beappreciated by one of ordinary skill in the art upon viewing thisdisclosure.

In an embodiment, the filter 214 may be configured to filter frequenciesabove and/or below a predetermined cut-off frequency, for example thefilter 214 may be configured as a low-pass filter, a high-pass filter, aband-pass filter, a band-stop filter, and/or any other suitable type offilter as would be appreciated by one of ordinary skill in the art uponviewing this disclosure. For example, the filter 214 may be configuredas a low-pass filter and may be configured to limit the bandwidth of themixed signal and/or to remove and/or substantially reduce the frequencycontent of the mixed compensated signal above a predetermined cut-offfrequency, thereby generating the filtered electrical signal.

In the embodiment of FIG. 3, an implementation of the transmitter 114 isillustrated. It is noted that in such an embodiment the circuit levelimplementation is provided for illustrative purposes and that a personskilled in the relevant arts will recognize suitable alternativeembodiments, configurations, and/or arrangements of such functionalunits which may be similarly employed. Any such functional unitembodiments may conceivably serve as elements of the disclosedimplementation.

In the embodiment of FIG. 3, the transmitter 114 may generally comprisea mixer 222, a filter 220, an ALNA 206 b, a duplexer 218, a high-Qfilter 216, and an antenna switch 226. Although the embodiment of FIG. 3illustrates a transmitter 114 comprising multiple distributed components(e.g., a mixer 222, a filter 220, an ALNA 206 b, a duplexer 218, ahigh-Q filter 216, and an antenna switch 226, each of which comprises aseparate, distinct component), in an alternative embodiment, a similartransmitter 114 may comprise similar components in a single, unitarycomponent. Alternatively, the functions performed by these components(e.g., the mixer 222, the filter 220, the ALNA 206 b, the duplexer 218,the high-Q filter 216, and the antenna switch 226) may be distributedacross any suitable number and/or configuration of like componentry, aswill be appreciated by one of ordinary skill in the art with the aid ofthis disclosure.

In an embodiment, the mixer 222 may be configured to receive a datasignal (e.g., from a logic unit) via electrical connections 152 and tooutput a mixed signal to the filter 220 (e.g., via electrical connection270). In an embodiment, the mixer 222 may configured similarly aspreviously disclosed, for example, as similarly disclosed with respectto the mixer 210 in FIG. 2. In an alternative embodiment, the mixer 222may be of any suitable type and/or configuration as would be appreciatedby one of ordinary skill in the art upon viewing this disclosure.

In an embodiment, the filter 220 may be configured to receive a mixedsignal from the mixer 222 (e.g., via electrical connections 270) and tooutput a filtered electrical signal to the ALNA 206 b (e.g., viaelectrical connection 268). In an embodiment, the filter 220 mayconfigured similarly as previously disclosed, for example, as similarlydisclosed with respect to the filter 214. In an alternative embodiment,the filter 220 may be of any suitable type and/or configuration as wouldbe appreciated by one of ordinary skill in the art upon viewing thisdisclosure.

In an embodiment, the ALNA 206 b may be configured to receive a filteredelectrical signal (e.g., via electrical connections 268) and to outputan amplified electrical signal to the duplexer 218 (e.g., via electricalconnection 266). In an embodiment, the ALNA 206 b may configuredsimilarly as disclosed below, for example, as similarly disclosed withrespect to the ALNA 206 a. In an alternative embodiment, the ALNA 206 bmay be of any suitable type and/or configuration as would be appreciatedby one of ordinary skill in the art upon viewing this disclosure.

In an embodiment, the duplexer 218 may be configured to receive anamplified electrical signal from the ALNA 206 b (e.g., via electricalconnections 266) and to output the amplified electrical signal to thehigh-Q filter 216 (e.g., via electrical connection 264). In anembodiment, the duplexer 218 may configured similarly as previouslydisclosed, for example, as similarly disclosed with respect to theduplexer 204. In an alternative embodiment, the duplexer 218 may be ofany suitable type and/or configuration as would be appreciated by one ofordinary skill in the art upon viewing this disclosure.

In an embodiment, the high-Q filter 216 may be configured to receive anamplified electrical signal from the duplexer 218 (e.g., via electricalconnections 264) and to output a band-pass filtered electrical signal tothe antenna switch 226 (e.g., via electrical connection 262). In anembodiment, the high-Q filter 216 may configured similarly as previouslydisclosed, for example, as similarly disclosed with respect to thehigh-Q filter 202. In an alternative embodiment, the high-Q filter 216may be of any suitable type and/or configuration as would be appreciatedby one of ordinary skill in the art upon viewing this disclosure.

In an embodiment, the antenna switch 226 may be configured to receive aband-pass filtered electrical signal from the high-Q filter 216 (e.g.,via electrical connection 262) and to output an electrical signal to theantenna 128 (e.g., via electrical connection 150). In an embodiment, theantenna switch 226 may be configured similarly as previously disclosed,for example, as similarly disclosed with respect to the antenna switch224. In an alternative embodiment, the antenna switch 226 may be of anysuitable type and/or configuration as would be appreciated by one ofordinary skill in the art upon viewing this disclosure.

In the embodiments of FIGS. 2-3, the ALNA 206 may be configured to causean electrical signal (e.g., the band-pass electrical signal) toexperience a gain, for example, a voltage gain, and therebyproportionally increase the voltage level of the electrical signal.Additionally or alternatively, in an embodiment, the ALNA 206 may befurther configured to convert a voltage signal to a current signal(e.g., a transconductance amplifier) or a current signal to a voltagesignal (e.g., a transimpedance amplifier) before or after applying again to the electrical signal. Not intending to be bound by theory,applying a gain factor of greater than one to the electrical signal mayincrease the voltage range over which the analog voltage signal can varyor swing, thereby improving the resolution and/or detectability of smallvariations of the electrical signal. For example, the electrical signalmay experience a gain by a factor of about 100, by a factor of about1,000, by a factor of about 10,000, by a factor of about 100,000, or anyother suitable gain factor as would be appreciated by one of ordinaryskill in the art upon viewing this disclosure. For example, a voltagesignal may experience a gain of about 1,000 and the voltage swing of thevoltage signal may increase from about 1 millivolt (mV) to about 1 volt(V). Additionally, in an embodiment, the ALNA 206 may be configured tohave an adjustable and/or a controllable gain, for example, via avariable gain controller, as will be disclosed herein. For example, theALNA 206 may be configured to be controlled by the logic unit 120 andmay be configured to adjust its gain in response to a control signal bythe logic unit 120, as will be disclosed herein. In an additional oralternative embodiment, the ALNA 206 may be configured to maintain asubstantially constant input impedance, for example, via adjusting avariable impedance controller, as will be disclosed herein.

In a conventional low noise amplifier (LNA) 400, as illustrated in FIG.4, the LNA 400 may generally comprise a plurality of resistors, aplurality of capacitors, and a plurality of transistors and may beconfigured to amplify an electrical signal. In an additional oralternative embodiment, the LNA 400 may further comprise one or moreinductors 414. In the embodiment of FIG. 4, the LNA 400 comprises adifferential input 402 (e.g., a non-inverting input 402 a and aninverting input 402 b), a differential output 404 (e.g., a non-invertingoutput 404 a and an inverting output 404 b), a feedback input 412, aplurality of biasing inputs 410 (e.g., biasing inputs 410 a-d) and maygenerally form a differential amplifier. In such an embodiment, theconventional LNA 400 may not be configured to provide an adjustable gainand/or may not be configured to maintain a substantially constant inputimpedance.

In the embodiment of FIG. 5, the ALNA 206 may generally comprise aplurality of resistors, a plurality of capacitors, a plurality oftransistors, and a variable impedance controller 600. In such anembodiment, the ALNA 206 may be configured to amplify an electricalsignal and to provide adjustable gain control and impedance and/or shuntresistance control (e.g., via the variable impedance controller 600), aswill be disclosed herein. In the embodiment of FIG. 5, the ALNA 206 maybe generally configured as a voltage amplifier (e.g., a Cascodeamplifier) comprising an amplifier input 502 and one or more currentflow paths coupled to an amplifier output 504, as will be disclosedherein. In an alternative embodiment, the ALNA 206 may be configured asa differential amplifier and/or any other suitable type and/orconfiguration of amplifier as would be appreciated by one of ordinaryskill in the art upon viewing this disclosure. Additionally, in such anembodiment, the ALNA 206 may further comprise common mode feedback(e.g., via electrical connection 510) and a negative feedback connectionbetween the amplifier input 502 and the amplifier output 504 via thevariable impedance controller 600. Further, in such an embodiment, theALNA 206 may comprise one or more of current steering inputs 512 (e.g.,current steering inputs 512 a-512 h) and one or more current flow paths514 (e.g., a first current flow path 514 a and a second current flowpath 514 b), as will be disclosed herein.

In an embodiment, as illustrated in FIG. 5, the gain of the ALNA 206 maybe adjusted (e.g., increased or decreased) by steering a current fromthe source 506 (e.g., a voltage source or a current source) towards aload (e.g., a mixer) coupled to the amplifier output 504 and/or steeringat least a portion of the current from the source 506 to the ground 508(e.g., an alternating current (AC) ground). For example, a logic unitmay apply a control signal (e.g., a voltage signal or a current signal)to one or more current steering inputs 512 a-512 f and, thereby steer atleast a portion of the current from the source 506 toward amplifieroutput 504. In such an embodiment, as the amount of current supplied toamplifier output 504 increases, the gain of the ALNA 206 may alsoincrease. In an embodiment, as the amount of current supplied toamplifier output 504 decreases (e.g., via sinking a portion of thecurrent to the ground 508), the gain of the ALNA 206 may also decrease.

In an embodiment, the gain of the ALNA 206 may be adjustable and may becontrollable by adjusting (e.g., increasing or reducing) the amount ofcurrent provided by the ALNA 206 to the output (e.g., amplifier output504) of the ALNA 206. For example, the ALNA 206 may be configured todeliver a current from a source 506 to the output of the ALNA 206 (e.g.,via the first current flow path 514 a and the amplifier output 504),thereby providing gain to an electrical signal. In an additionalembodiment, the ALNA 206 may be configured to at least partially reducea current being supplied from the source 506 to a load (e.g., via thefirst current flow path 514 a and the amplifier output 504), forexample, by diverting at least a portion of the current to a ground 508(e.g., via the second current flow path 514 b), thereby reducing thegain provided by the ALNA 206.

For example, in the embodiment of FIG. 5, the ALNA 206 may be configuredsuch that a current is provided in the direction of one or more nodes(e.g., node 515) from the source 506 (e.g., a voltage source or acurrent source), for example, via a third current flow path 516. Notintending to be bound by theory, the current in any node (e.g., node515) is about zero, therefore the current being supplied to the node 515via the third current flow path 516 will exit the node 515 via the firstcurrent flow path 514 a and/or the second current flow path 514 b, whenso configured. In an embodiment, the first current flow path 514 a maybe configured to selectively provide a current flow path between thenode 515 and the amplifier output 504. For example, the current steeringinput 512 a may configured to be controllable (e.g., via a voltagesignal from a logic unit) and to selectively enable a current flow path,for example, applying a voltage (e.g., a forward biasing voltage) to thecurrent steering input 512 a provides a current flow path via the firstcurrent flow path 514 a, thereby delivering a current to the amplifieroutput 504. Additionally, in an embodiment, the second current flow path514 b may be configured to selectively provide a current flow pathbetween the node 515 and the ground 508 (e.g., an alternating current(AC) ground). In such an embodiment, the current steering input 512 bmay configured to be controllable (e.g., via a voltage signal from thelogic unit) and to selectively enable a current flow path, for example,applying a voltage (e.g., a forward biasing voltage) to the currentsteering input 512 b provides a current flow path via the second currentflow path 514 b, thereby sinking the current to the ground 508. In anadditional or alternative embodiment, where the ALNA 206 comprises morethan one current steering flow paths in parallel with respect to eachother and may be scaled or weighted (e.g., binary weighted) to providevarying levels of current flow. For example, the ALNA 206 may beconfigured such that each subsequent current steering flow path providesabout half of the current flow of the previous current steering flowpath. In an alternative embodiment, the ALNA 206 may be configured suchthat each current steering flow path provides the same amount of currentflow. In an alternative embodiment, the current steering flow paths maybe any suitable type and/or configuration as would be appreciated by oneof ordinary skill in the art upon viewing this disclosure.

In an embodiment, the variable impedance controller 600 may becontrollable (e.g., via a logic unit) and may be generally configured toprovide an adjustable impedance and/or shunt resistance, for example,for the purposes of adjusting the feedback resistance, the shuntresistance, the input impedance, and/or the output impedance of the ALNA206.

In an embodiment, the variable impedance controller 600 may generallycomprise one or more transistors coupled in parallel with one or moreresistive elements (e.g., a resistor). For example, in the embodiment ofFIG. 6, the transistors may form a transmission gate in parallel with aresistor, thereby forming a resistive module 606. In such an embodiment,the resistive module 606 may be configured to be controllable (e.g., viaa logic unit) and to provide an adjustable resistance, for example, viaselectively providing more than resistive current flow paths (e.g., afirst resistive current flow path 610 and a second resistive currentflow path 612). In an embodiment, the first resistive current flow path610 may comprise an at least partially resistive flow path, for example,through one or more resistive elements (e.g., a resistor). Additionally,in such an embodiment, the second resistive current flow path 612 maycomprise a substantially less resistive flow path with respect to thefirst resistive flow path 610. For example, the second resistive flowpath 610 may comprise a flow path across the gates of one or moretransistors, when so configured. In an alternative embodiment, aresistive module may comprise any other suitable number, type, and/orconfigurations of resistive current flow paths as would be appreciatedby one of ordinary skill in the art upon viewing this disclosure.Additionally, in an embodiment, the resistive module 606 may beconfigured to select a resistive current flow path upon the applicationof a control signal (e.g., a voltage signal) to the gates of one or moretransistors (e.g., via a logic unit). For example, in the embodiment ofFIG. 6, one or more transistors of the resistive module 606 may beconfigured such that applying a voltage (e.g., a forward biasingvoltage) to the gates (e.g., gate terminals 608 a-608 m) of the one ormore transistors enables the second resistive current flow path 612,thereby bypassing the first resistive current flow path 610.Additionally, in such an embodiment, one or more transistors of theresistive module 606 may be configured such that in an absence of avoltage being applied to the gates (e.g., gate terminals 608 a-608 m) ofthe one or more transistors disables the second resistive current flowpath 612, thereby enabling the first resistive current flow path 610.

In an embodiment, the variable impedance controller 600 may furthercomprise a plurality of resistive modules 606 (e.g., resistive modules606 a-606 f) and may be configured to provide an adjustable impedanceand/or resistance for a current flow path between an input terminal 602and an output terminal 604 of the variable impedance controller 600. Insuch an embodiment, the plurality of resistive modules 606 may becoupled in series and/or parallel with respect to each other. In anembodiment, each resistive module 606 may be configured to respondindividually to a control signal. In an alternative embodiment, two ormore of the resistive modules 606 may be configured to respond jointlyin response to a control signal.

In an embodiment, an amplification method utilizing the ALNA 206 and/ora system comprising an ALNA 206 is disclosed herein. In an embodiment,as illustrated in FIG. 7, an amplification method may generally comprisethe steps of receiving an electrical signal 702, adjusting an inputimpedance and gain factor 704, amplifying the electrical signal 706, andoutputting the amplified electrical signal 708. In an additionalembodiment, an amplification method may further comprise receiving anelectrical signal, readjusting the input impedance and/or the gainfactor, amplifying the electrical signal, and outputting the amplifiedelectrical signal.

Referring to FIG. 8, an impedance response (e.g., a Smith chart) for theALNA 206 is provided. In an embodiment, prior to adjusting the gain ofthe ALNA 206, the ALNA 206 may be about impedance matched and located atan impedance matched point 800. In an embodiment, adjusting the gain ofthe ALNA 206 may result in an impedance change 804 away from theimpedance matched point 800. In an embodiment, the variable impedancecontroller 600 may be employed to apply a compensation impedance change802, for example, by adjusting the impedance and/or resistance of thevariable feedback controller 600 and/or the feedback resistance of theALNA 206, as previously disclosed. For example, in the embodiment ofFIG. 6, a logic unit may apply a control signal (e.g., a voltage signalor a current signal) to the gates (e.g., gate terminals 608 a-608 m) ofone or more transistors of the resistive module 606 and, thereby mayadjust the impedance and/or resistance of the variable impedancecontroller 600. In such an embodiment, the variable impedance controller600 may be adjusted such that the resulting compensation impedancechange 802 may offset the impedance change 804 and, thereby reconfigurethe ALNA 206 to be about impedance matched and located at about theimpedance matched point 800, as illustrated in FIG. 8. In an embodiment,the impedance and/or resistance of the variable impedance controller 600and the gain of the ALNA 206 may be adjusted substantiallysimultaneously. For example, the variable impedance controller 600 andthe gain of the ALNA 206 may be adjusted within about one second of eachother. Additionally or alternatively, the variable impedance controller600 and the gain of the ALNA 206 may be adjusted at least partiallyconcurrently, for example, the gain of the ALNA 206 may first begin tobe adjusted, then the variable impedance controller 600 may also beginto adjust, and the adjustment of the gain of the ALNA 206 may becompleted prior to the completion of the variable impedance controller600 adjustment. Alternatively, the variable impedance controller 600 mayfirst begin to be adjusted, then the gain of the ALNA 206 may also beginto adjust, and the adjustment of the variable impedance controller 600may be completed prior to the completion of the adjustment of the gainof the ALNA 206. Alternatively, while adjusting the gain of the ALNA206, the variable impedance controller 600 may also begin and completean adjustment prior to completing the gain adjustment of the ALNA 206.Alternatively, while adjusting the variable impedance controller 600,the gain of the ALNA 206 may also begin and complete an adjustment priorto completing the adjustment of the variable impedance controller 600.Additionally, in such an embodiment, the impedance response of the ALNA206 may be substantially constant.

In an embodiment, the process of receiving an electrical signal,adjusting an input impedance and gain factor, amplifying the electricalsignal, and outputting the amplified electrical signal may be repeated.For example, in a manner similar to that disclosed herein, the gainand/or the impedance (e.g., the variable impedance controller 600) ofthe ALNA 206 may be adjusted and, thereby amplify an electrical signalto generate an amplified electrical signal while maintaining the inputimpedance of the ALNA 206 to be substantially constant.

In an embodiment, an ALNA 206, a system comprising an ALNA 206, and/oran amplification method employing a system and/or an ALNA 206, asdisclosed herein or in some portion thereof, may be advantageouslyemployed during mobile device operations. As will be appreciated by oneof ordinary skill in the art, conventional methods of amplifying anelectrical signal may not have the capabilities to provide an adjustablegain and/or to maintain a substantially constant input impedance. In anembodiment, the ALNA 206 enables an adjustable gain while substantiallysimultaneously adjusting an input impedance, as previously disclosed.For example, the performance of the receiver 112, the transmitter 114,and/or the mobile device 100 can be improved and provide a substantiallystable frequency response. Therefore, the methods disclosed hereinprovide a means by which the performance of the receiver 112, thetransmitter 114, and/or the mobile device 100 can be improved.

At least one embodiment is disclosed and variations, combinations,and/or modifications of the embodiment(s) and/or features of theembodiment(s) made by a person having ordinary skill in the art arewithin the scope of the disclosure. Alternative embodiments that resultfrom combining, integrating, and/or omitting features of theembodiment(s) are also within the scope of the disclosure. Wherenumerical ranges or limitations are expressly stated, such expressranges or limitations should be understood to include iterative rangesor limitations of like magnitude falling within the expressly statedranges or limitations (e.g., from about 1 to about 10 includes, 2, 3, 4,etc.; greater than 0.10 includes 0.11, 0.12, 0.13, etc.). For example,whenever a numerical range with a lower limit, R_(l), and an upperlimit, R_(u), is disclosed, any number falling within the range isspecifically disclosed. In particular, the following numbers within therange are specifically disclosed: R=R_(l)+k*(R_(u)−R_(l)), wherein k isa variable ranging from 1 percent to 100 percent with a 1 percentincrement, i.e., k is 1 percent, 2 percent, 3 percent, 4 percent, 5percent, . . . , 50 percent, 51 percent, 52 percent, . . . , 95 percent,96 percent, 97 percent, 98 percent, 99 percent, or 100 percent.Moreover, any numerical range defined by two R numbers as defined in theabove is also specifically disclosed. The use of the term aboutmeans±10% of the subsequent number, unless otherwise stated. Use of theterm “optionally” with respect to any element of a claim means that theelement is required, or alternatively, the element is not required, bothalternatives being within the scope of the claim. Use of broader termssuch as comprises, includes, and having should be understood to providesupport for narrower terms such as consisting of, consisting essentiallyof, and comprised substantially of. Accordingly, the scope of protectionis not limited by the description set out above but is defined by theclaims that follow, that scope including all equivalents of the subjectmatter of the claims. Each and every claim is incorporated as furtherdisclosure into the specification and the claims are embodiment(s) ofthe present disclosure. The discussion of a reference in the disclosureis not an admission that it is prior art, especially any reference thathas a publication date after the priority date of this application. Thedisclosure of all patents, patent applications, and publications citedin the disclosure are hereby incorporated by reference, to the extentthat they provide exemplary, procedural, or other details supplementaryto the disclosure.

While several embodiments have been provided in the present disclosure,it should be understood that the disclosed systems and methods might beembodied in many other specific forms without departing from the spiritor scope of the present disclosure. The present examples are to beconsidered as illustrative and not restrictive, and the intention is notto be limited to the details given herein. For example, the variouselements or components may be combined or integrated in another systemor certain features may be omitted, or not implemented.

In addition, techniques, systems, subsystems, and methods described andillustrated in the various embodiments as discrete or separate may becombined or integrated with other systems, modules, techniques, ormethods without departing from the scope of the present disclosure.Other items shown or discussed as coupled or directly coupled orcommunicating with each other may be indirectly coupled or communicatingthrough some interface, device, or intermediate component whetherelectrically, mechanically, or otherwise. Other examples of changes,substitutions, and alterations are ascertainable by one skilled in theart and could be made without departing from the spirit and scopedisclosed herein.

What is claimed is:
 1. A mobile device comprising: an antenna; areceiver coupled to the antenna; and a transmitter coupled to theantenna, wherein the receiver, the transmitter, or both comprise a lownoise amplifier comprising an adjustable gain and a variable impedancecontroller, the variable impedance controller is configured to adjust aninput impedance of the low noise amplifier by selectively providing morethan one resistive flow path, and the low noise amplifier is configuredto sink current and to adjust a shunt resistance simultaneously using aplurality of current flow paths, wherein a first current flow pathextends between a source node and ground and a second current flow pathextends between the source node and a load without connecting to theground.
 2. The mobile device of claim 1, wherein the variable impedancecontroller comprises one or more transistors and one or more resistorsin parallel with the one or more transistors.
 3. The mobile device ofclaim 2, wherein the variable impedance controller further comprises twoor more of the transistors in parallel with the resistors in series witheach other.
 4. The mobile device of claim 2, wherein the variableimpedance controller further comprises two or more of the transistors inparallel with the resistors in parallel with each other.
 5. The mobiledevice of claim 4, wherein the low noise amplifier comprises two or morecurrent flow paths in parallel, and wherein the current flow paths inparallel comprise a connection to the ground.
 6. The mobile device ofclaim 1, wherein simultaneously is within about one second of eachother.
 7. The mobile device of claim 1, wherein simultaneously is atleast partially concurrent.
 8. A method comprising: receiving anelectrical signal; simultaneously adjusting an input impedance and again factor, wherein the input impedance is adjusted by selectivelyproviding more than one resistive flow path, wherein the gain factor isadjusted by sinking current using a plurality of current flow paths,wherein a first current flow path extends between a source node andground and a second current flow path extends between the source nodeand a load without connecting to the ground; amplifying the electricalsignal, thereby producing an amplified signal; and outputting theamplified signal.
 9. The method of claim 8, wherein the input impedanceis adjusted by adjusting a shunt resistance.
 10. The method of claim 9,wherein the shunt resistance is adjusted by configuring a variableimpendence controller.
 11. The method of claim 10, wherein the inputimpedance is maintained constant.
 12. The method of claim 11, whereinthe gain factor is adjusted sinking at least a portion of the current tothe ground.
 13. The method of claim 11, wherein at least a portion ofthe current is diverted away from the load.
 14. The method of claim 8,wherein substantially simultaneously is within about one second of eachother.
 15. The method of claim 8, wherein simultaneously is at leastpartially concurrent.
 16. A mobile device comprising: an antenna; areceiver coupled to the antenna; and a transmitter coupled to theantenna, wherein the receiver and the transmitter each comprise a lownoise amplifier comprising an adjustable gain and a variable impedancecontroller, the variable impedance controller is configured to adjust aninput impedance of the low noise amplifier by selectively providing morethan one resistive flow path, and the low noise amplifier is configuredto sink current and to adjust a shunt resistance simultaneously using aplurality of current flow paths, wherein a first current flow pathextends between a source node and ground and a second current flow pathextends between the source node and a load without connecting to theground, and wherein a first resistive flow path extends between thesource node and the ground and a second resistive flow path extendsbetween the source node and a load without connecting to the ground. 17.The mobile device of claim 16, wherein the variable impedance controllercomprises a plurality of transistors in parallel with a plurality ofresistors.
 18. The mobile device of claim 16, wherein simultaneously iswithin one second of each other.
 19. The mobile device of claim 16,wherein at least a portion of the current is sunk to the ground.